Ionizing Radiation

What is Ionizing Radiation?

Ionizing radiation is a type of energy released by atoms that travel in the form of particles (alpha, beta, or neutrons) or electromagnetic waves (X-rays or gamma rays). The energy emitted is in the form of ionizing radiation. Radioactivity is the spontaneous emission of radiation in the form of high energy photons resulting from a nuclear reaction. It is a random process that occurs at the level of individual atoms. Radioactive substances like thorium, uranium, and radium produce radiation and they also produce a lot of energy. They all can easily knock electrons out of atoms and form charged particles.


Ionizing Radiation Definition

Ionizing radiation is radiation with great energy so that during an interaction with the atom, it can remove tightly bound electrons from the orbit of an atom, causing the atom to be changed from their neutral state. Ionizing radiation occurs in two forms- waves or particles. It is made up of ions, atoms, or energetic subatomic particles moving at high speeds and electromagnetic waves on the high-energy end of the electromagnetic spectrum.


X-rays, gamma rays and the ultraviolet part of the electromagnetic spectrum. It has more energy than non-ionizing radiation, enough to cause chemical changes by breaking bonds. 


There are 3 main types of ionizing radiation:

  • Alpha particles 

  • Beta particles

  • Gamma rays 


Alpha Particles

Alpha particles are particulate radiations with hugely ionizing form. Alpha particles are slower and heavier than x-rays and gamma rays. These particles become dangerous when they are inhaled. Radon is odorless, colorless, and tasteless gas which comes from the decay of the element radium. The alpha particles from radon are about 20 times as effective as X rays and gamma rays at causing breathing problems. Radium occurs naturally in earth rock's and is made primarily of alpha particles. 


During the process of nuclear decay, the liberated energy is shared between the daughter nucleus and the alpha particle. Alpha particles dissipate their energy during collisions by two mechanisms: electron and ionization excitation. The alpha particle with high charge is relative to other forms of nuclear radiation and gives greater ionization power.


Uses of Alpha Particles

  • They are used as smoke detectors.

  • They are commonly used in space probes

  • They are also used in radiotherapy to treat cancer.


Beta Particles

Beta particles are electrons which are smaller than alpha particles. They can easily penetrate through human skin or cause tissue damage. Beta particles can be inhaled if they contaminate food and water supplies. Beta-decay is the production of beta particles. Beta particles denoted by Greek letters (β).


They normally occur in nuclei that have too many neutrons to achieve stability. They have a mass of half of one-thousandth of the mass of a proton. Their light mass means that they lose energy very quickly through interaction with matter. Beta particles are also found in the radioactive products of nuclear fission. They are also found in the radioactive chain of thorium, uranium, and actinium.


Uses of Beta Particles

  • They are used in thickness detectors for the quality control of thin materials.

  • Fluorine-18 is used as a tracer for PET.

  • They also help in the treatment of eye and bone cancers.

  • Tritium is used for emergency lighting.


Gamma Rays

It is a packet of electromagnetic energy emitted by the nucleus of some radioactive elements. Photons of gamma rays are the most energetic photons in the electromagnetic spectrum. They are basically emitted from an excited nucleus. 


Waves of gamma rays have the shortest wavelength. The high energy of gamma rays enables them to pass through many kinds of material including human tissues. Radiations of gamma rays are penetrating and interact with matter through ionization. 


They are also easily found in the radiation decay of thorium, uranium, etc. Gamma radiations are easily found in rocks, soil, and in our water and food.


Uses of Gamma Rays

  • Cobalt-60 used in industrial radiography

  • They are also used in pasteurization

  • Caesium-137 used in measurement and control of the flow of liquid in industrial processes.

  • They are also used in leveling gauges for packaging of food, and other products.

FAQ (Frequently Asked Questions)

1.What are the Properties of Ionizing Radiation?

The properties of ionizing radiations are:

  • They travel in straight lines and are invisible.

  • It can pass through low-density material more readily than through high-density material.

  • They are being able to penetrate matter which is opaque to light and they have a photographic action similar to that of light.

  • Their penetrating ability depends on their wavelength.

  • Both X-rays and gamma rays travel at the speed of light.

  • They can easily cause chemical changes by breaking bonds.

  • They have a shorter wavelength than UV rays.

  • They can cause serious damage if it gets into the body due to their high ionization power.

2. Is Ionizing Radiation Always Harmful?

No. Ionizing radiation gets harmful to an organism when the total amount of it gets too high. If the amount of ionizing radiation exposure is very low, our bodies can handle a few damaged molecules easily, so that there is no net harm done to our bodies. 


When the dose is high enough, ionizing radiation causes two types of harm to humans, tissue damage, and cancer.


Direct tissue damage happens when molecules are broken apart. This can lead to radiation burns, sickness, and even death. Cancer results when the cells receive a small amount of damage to the genes that cause the cell to pursue uncontrolled growth.